Synthesis Report for the ERTDI-funded project: 2005-W-MS-39

The main threat to surface water quality in Ireland and much of Western Europe is eutrophication, due to the excessive inputs of agricultural- and municipal-derived plant nutrients. Such nutrients have widespread ecological effects, notably the increased growth of aquatic plants and algae. Under the terms of the European Union Water Framework Directive (WFD), participating nations, including Ireland, must achieve good water status for all surface waters by 2015. Some 30% of Irish running waters currently fail to meet this objective, largely due to eutrophication, and require significant efforts to bring them to the required standard. Although the quantitative relationships between nutrient levels, primary producers and their consumers are reasonably well established for standing waters, scientific understanding of these links in running waters is weaker, due to their greater environmental complexity. The aims of this study were to investigate the relationships between plant nutrients, primary producers and their invertebrate consumers in running waters and to identify the main factors that affect this relationship.

The study had two phases:

A descriptive phase where the standing stock of algae and invertebrates in Munster streams across nutrient and riparian shade gradients was investigated; and

A second phase which experimentally tested the roles of the various factors that drive the growth of benthic algae in a single nutrient-impacted stream – the Owennagearagh Stream, a tributary of the River Lee in County Cork.

Also available for download:

Print-Quality Version (i.e. high resolution PDF) of STRIVE Report 60

Final Report: IMPLANT: The Impact of Plant Nutrients on Primary Productivity in Running Waters: Evaluating the Risk to Stream Ecological Status